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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
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package javax.sql.rowset.serial;
import java.sql.*;
import java.io.*;
import java.util.*;
/**
* A serialized mapping of a <code>Ref</code> object, which is the mapping in the
* Java programming language of an SQL <code>REF</code> value.
* <p>
* The <code>SerialRef</code> class provides a constructor for
* creating a <code>SerialRef</code> instance from a <code>Ref</code>
* object and provides methods for getting and setting the <code>Ref</code> object.
*
* <h2> Thread safety </h2>
*
* A SerialRef is not safe for use by multiple concurrent threads. If a
* SerialRef is to be used by more than one thread then access to the SerialRef
* should be controlled by appropriate synchronization.
*
* @since 1.5
*/
public class SerialRef implements Ref, Serializable, Cloneable {
/**
* String containing the base type name.
* @serial
*/
private String baseTypeName;
/**
* This will store the type <code>Ref</code> as an <code>Object</code>.
*/
@SuppressWarnings("serial") // Not statically typed as Serializable
private Object object;
/**
* Private copy of the Ref reference.
*/
@SuppressWarnings("serial") // Not statically typed as Serializable; checked in writeObject
private Ref reference;
/**
* Constructs a <code>SerialRef</code> object from the given <code>Ref</code>
* object.
*
* @param ref a Ref object; cannot be <code>null</code>
* @throws SQLException if a database access occurs; if <code>ref</code>
* is <code>null</code>; or if the <code>Ref</code> object returns a
* <code>null</code> value base type name.
* @throws SerialException if an error occurs serializing the <code>Ref</code>
* object
*/
public SerialRef(Ref ref) throws SerialException, SQLException {
if (ref == null) {
throw new SQLException("Cannot instantiate a SerialRef object " +
"with a null Ref object");
}
reference = ref;
object = ref;
if (ref.getBaseTypeName() == null) {
throw new SQLException("Cannot instantiate a SerialRef object " +
"that returns a null base type name");
} else {
baseTypeName = ref.getBaseTypeName();
}
}
/**
* Returns a string describing the base type name of the <code>Ref</code>.
*
* @return a string of the base type name of the Ref
* @throws SerialException in no Ref object has been set
*/
public String getBaseTypeName() throws SerialException {
return baseTypeName;
}
/**
* Returns an <code>Object</code> representing the SQL structured type
* to which this <code>SerialRef</code> object refers. The attributes
* of the structured type are mapped according to the given type map.
*
* @param map a <code>java.util.Map</code> object containing zero or
* more entries, with each entry consisting of 1) a <code>String</code>
* giving the fully qualified name of a UDT and 2) the
* <code>Class</code> object for the <code>SQLData</code> implementation
* that defines how the UDT is to be mapped
* @return an object instance resolved from the Ref reference and mapped
* according to the supplied type map
* @throws SerialException if an error is encountered in the reference
* resolution
*/
public Object getObject(java.util.Map<String,Class<?>> map)
throws SerialException
{
map = new Hashtable<String, Class<?>>(map);
if (object != null) {
return map.get(object);
} else {
throw new SerialException("The object is not set");
}
}
/**
* Returns an <code>Object</code> representing the SQL structured type
* to which this <code>SerialRef</code> object refers.
*
* @return an object instance resolved from the Ref reference
* @throws SerialException if an error is encountered in the reference
* resolution
*/
public Object getObject() throws SerialException {
if (reference != null) {
try {
return reference.getObject();
} catch (SQLException e) {
throw new SerialException("SQLException: " + e.getMessage());
}
}
if (object != null) {
return object;
}
throw new SerialException("The object is not set");
}
/**
* Sets the SQL structured type that this <code>SerialRef</code> object
* references to the given <code>Object</code> object.
*
* @param obj an <code>Object</code> representing the SQL structured type
* to be referenced
* @throws SerialException if an error is encountered generating the
* the structured type referenced by this <code>SerialRef</code> object
*/
public void setObject(Object obj) throws SerialException {
try {
reference.setObject(obj);
} catch (SQLException e) {
throw new SerialException("SQLException: " + e.getMessage());
}
object = obj;
}
/**
* Compares this SerialRef to the specified object. The result is {@code
* true} if and only if the argument is not {@code null} and is a {@code
* SerialRef} object that represents the same object as this
* object.
*
* @param obj The object to compare this {@code SerialRef} against
*
* @return {@code true} if the given object represents a {@code SerialRef}
* equivalent to this SerialRef, {@code false} otherwise
*
*/
public boolean equals(Object obj) {
if (this == obj) {
return true;
}
if(obj instanceof SerialRef) {
SerialRef ref = (SerialRef)obj;
return baseTypeName.equals(ref.baseTypeName) &&
object.equals(ref.object);
}
return false;
}
/**
* Returns a hash code for this {@code SerialRef}.
* @return a hash code value for this object.
*/
public int hashCode() {
return (31 + object.hashCode()) * 31 + baseTypeName.hashCode();
}
/**
* Returns a clone of this {@code SerialRef}.
* The underlying {@code Ref} object will be set to null.
*
* @return a clone of this SerialRef
*/
public Object clone() {
try {
SerialRef ref = (SerialRef) super.clone();
ref.reference = null;
return ref;
} catch (CloneNotSupportedException ex) {
// this shouldn't happen, since we are Cloneable
throw new InternalError();
}
}
/**
* readObject is called to restore the state of the SerialRef from
* a stream.
*/
private void readObject(ObjectInputStream s)
throws IOException, ClassNotFoundException {
ObjectInputStream.GetField fields = s.readFields();
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